<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
    /*  
      margin:100px 四个方向全部改变
      margin:100px 200px;  就是上下100px  左右200px
      margin:100px 200px 300px;上100px 左右200 下300
      margin:100px 200px 300px 400px;顺时针
      */



    div{
        width: 100px;
        height: 100px;
        background:yellow;
        margin:100px 200px 300px;
    }
    </style>
</head>
<body>
    <div>

    </div>
</body>
</html>